From mboxrd@z Thu Jan 1 00:00:00 1970 From: Francois Romieu Subject: Re: r8169 auto speed down issue Date: Sat, 30 Mar 2013 13:42:56 +0100 Message-ID: <20130330124256.GA19236@electric-eye.fr.zoreil.com> References: <4EECA12DD88643FD9006350514D96C8E@realtek.com.tw> <20130328231955.GA26182@electric-eye.fr.zoreil.com> <83FC3118294143DC81063B29EF570FC1@realtek.com.tw> <20130329072056.GA31269@electric-eye.fr.zoreil.com> <555174DCA0B0431BB3AE9CCD464E5896@realtek.com.tw> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, bowgotsai@google.com, "'Ryankao'" To: hayeswang Return-path: Content-Disposition: inline In-Reply-To: <555174DCA0B0431BB3AE9CCD464E5896@realtek.com.tw> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org hayeswang : [...] > Sorry for my unclear descriptor. I just think a case that the nic suspends or > shutdowns without cable plugging. Then, the cable is plugged again. If the nic > speed down to 10M and the link partner force 100M, the issue appears again. If > the nic doesn't speed down for normal link partner, it requires more power > when the linking recovers. Yes. The nic can not guess what the user values most: power saving in a stable link layer configuration vs ability to detect and adapt to a yet unseen configuration. It could be a reason why EEE exists. > Finally, I determine to set the speed to 10M when the link partner supports > 10M. And for the other case, setting the speed to 100M. This avoids the giga > nic to keep the speed to 1000M, and could fix this issue. > However, I wonder if there is a switch which forces the speed to giga. We can check if the partner supports 100M too. It's almost free and it will avoid this problem. -- Ueimor